1. Line colander with four layers of cheesecloth or 2 layers of food-safe paper towels and set over large bowl. Combine milk, salt, and vinegar or lemon juice in microwave-safe glass 1-quart liquid measure. Microwave on high heat until lightly bubbling around edges, 2 to 4 minutes (milk should register about 165°F on an instant-read thermometer). Remove from microwave, and stir gently for 5 seconds. Milk should separate into solid white curds and translucent liquid whey. If not, microwave for 30 seconds longer. Repeat until fully separated.

2. Using slotted spoon or wire skimmer, transfer curds to prepared colander, cover exposed top with plastic wrap, and allow to drain until desired texture is reached. Store in covered container in refrigerator for up to 5 days.